The present invention relates to computer support of multiple display types.
Present computer systems provide a certain amount of flexibility in combining multiple computer displays and display types to a single personal computer, workstation, or embedded system. For example, under the Microsoft Windows 98 operating system, it is possible to simultaneously display images on two displays, but each display must be connected to a video adapter card attached to an ISA or PCI bus via its own slot. The computer must be configured (not in real time) to support the two different adapter cards and the displays attached to them. Graphic libraries and drivers must be identified and employed for each output display type. Different displays cannot be easily swapped without extensive configuration.
The following patents relate to the display portability problem addressed above: U.S. Pat. No. 5,960,213, to Wilson, entitled “Dynamically Reconfigurable Multi-Function PCI Adapter Device; U.S. Pat. No. 5,948,091, to Kerigan et al., entitled “Universal Digital Display Interface”; U.S. Pat. No. 5,910,180, to Flory et al., entitled “Context Virtualizing Device Driver Architecture”; U.S. Pat. No. 5,883,642, to Thomas et al., entitled “Programmable Retargeter Method and Apparatus”; U.S. Pat. No. 5,799,204, to Pesto, Jr., entitled “System Utilizing BIOS-Compatible High Performance Video Controller Being Default Controller at Boot-Up and Capable of Switching to Another Graphics Controller After Boot-Up”; U.S. Pat. No. 5,752,032, to Keller et al., entitled “Adaptive Device Driver Using Controller Hardware Sub-Element Identifier”; and U.S. Pat. No. 5,606,657, to Dennison et al., entitled “Virtual Graphics Processor for Embedded Real Time Display Systems”. However, unlike with the present invention, none of these solutions provide a single display adapter than can simultaneously handle and switch between multiple displays and display types.
Furthermore, the existence of both raster and stroke display types renders it difficult to use raster-oriented graphics applications with stroke display types. For example, Visual Applications Builder (VAPS®) formats, which is a common tool in the industry for building interactive display application data as graphics or generated code, are unable to drive stroke displays or to properly work with hybrid stroke/raster displays in both modes. The following patents relate generally to this problem, but none provide the ability of the present invention to drive stroke and hybrid displays using VAPS® formats: U.S. Pat. No. 5,499,325, to Dugan, Jr., entitled “Brightness Controls for Visual Separation of Vector and Raster Information”; U.S. Pat. No. 4,635,050, to Grothe et al., entitled “Dynamic Stroke Priority Generator for Hybrid Display”; U.S. Pat. No. 4,631,532, to Grothe, entitled “Raster Display Generator for Hybrid Display System”; and U.S. Pat. No. 4,055,004, to Chase, entitled “Full Color Hybrid Display for Aircraft Simulators.